Providing stability to a magnetoresistive (MR) read head is highly desirable.
This invention relates to a MR head having a read sensor and an inductive write transducer. More particularly, the invention is directed to improving the magnetic stability by regulating the bias, particularly the bias current, through the MR head.
Existing magnetic storage systems using MR heads to read data from magnetic media and to write data onto magnetic media suffer instability in relation to the MR head. This instability is caused when the bias current to the MR head is switched off during the period when a write current signal is applied to the inductive write transducer. The instability can cause the loss of data on the magnetic media. This can be destructive, costly and very burdensome.
One manner of avoiding instability is to maintain the bias current to the read sensor at its operational level for reading even though the MR head is in the mode for writing under a current signal being applied to the inductive write transducer. A disadvantage of this system is that it is costly on power, even when this bias current is in the range of several milliamps. This is particularly onerous in computers which are battery operated, such as laptop and notebook computers where such wasted current can be an overall unacceptable cost to the battery life of a computer.
There is a need to provide an improved method of regulating the stability of a MR head while at the same time not rendering the stability process costly in the sense of power usage.